Spin, linear, and orbital friction welding techniques are well-known solid-state welding processes for joining component parts. However, the spin friction welding process is limited in that it can only be used for joining parts whose faying surfaces are parallel during the welding operation. Even though linear and orbital friction welding processes may not be similarly constrained, they require more complex and expensive machinery than does spin friction welding. More significantly, with linear and orbital friction welding methods, the welding surface of the workpiece may have no geometric variation along the axis of oscillation, making welding of components having non-uniform shapes difficult.